As far as lasting a lifetime, I don't think they mean that it will actually last a lifetime, but they do offer to replace battery and/or led free for your lifetime--with the standard handling fee, which ends up being about what it costs to buy a new one. I've had mine for several years now, and use them constantly. Mine are just now beginning to be hard to light; either the switch is getting worn or battery is getting low. I plan to send them back in, or just replace them with new ones, because I like them so much. They're well worth the price. A couple of mine have even been through the washer and dryer and still work (although the dryer deformed the plastic case a little). That's good to know if you plan to use yours in the outdoors--if you drop it in the water, it'll still work. The one thing that would make this light perfect, and the only reason I didn't give it 5 stars, is that it needs some way to turn it on permanently. As it is you have to keep the button pressed down to make it light. A great tool. Highly recommended!